Portion of an audio amplifier



FIG. 1 is a top plan view of a portion of an audio amplifier showing my new design

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a front perspective view thereof;

FIG. 7 is a left side perspective view thereof;

FIG. 8 is a right side perspective view thereof; and,

FIG. 9 is a top perspective view thereof.

The broken line showing of a portion of an amplifier in the Figures is environmental only and forms no part of the claimed design. The bottom plan view of the design disclosed in the Figures is unornamented. 

The ornamental design for a portion of an audio amplifier, as shown and described. 